• Journal of Korean Society of Environmental Engineers
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• v.31 no.10
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• pp.893-900
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• 2009

To estimate the contribution of epiphytic algae attached on reed to organic matter production in constructed wetland, primary productivity by epiphytic algae was investigated in two sub-wetlands (Banweol and Donhwa wetlands) of the Sihwa Constructed Wetland (CW) with different chemistry of inflows. Chlorophyll a concentration of epiphytic algae was higher in the Banweol wetland (range:37~3,581 mgChl.a/$m^2$surface stem, average:655 mgChl.a/$m^2$surface stem) than the Donhwa wetland (range:87~2,093 mgChl.a/$m^2$surface stem, average:527 mgChl.a/$m^2$surface stem). In contrast, assimilation number (AN) representing photosynthetic activity was higher in the Donhwa wetland with low TN/TP ratio than the Banweol wetland. A negative correlation (r=0.46) was observed between TN/TP ratios of inflows and AN in two wetlands, implying that high photosynthetic activity of epiphytic algae may be related with low TN/TP ratio. The areal primary productivity ranged from 307 to 2,473 mgC/$m^2$/day in the Banweol wetland and from 756 to 2,096 mgC/$m^2$/day in the Donghwa wetland, showing high productivity in summer. Average primary production was lower in the Banweol wetland (1,166 mgC/$m^2$/day) than the Donghwa wetland (1,467 mgC/$m^2$/day), although the standing crop (as chlorophyll a concentration) was high in the Banweol wetland. This result may be due to the low photosynthetic activity of epiphytic algae in the Banweol wetland with high TN/TP ratio. The annual primary production (300 tonC/year) of epiphytic algae contributed 33% of the total production in the Sihwa CW. An excessive organic matter production in constructed wetland can negatively affect the efficiency of water treatment. Therefore, the role of epiphytic algae should be considered in management of constructed wetland for water treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.6 no.1
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• pp.41-47
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• 1977

This study was designed to evaluate the nutritive value of pearl barley. Forty males and the same number of females of albino rats, the Leuise strain, weighing from 52.1g to 59.1g were divided into eight experimental groups, five males and females were composed of one group. A group: casein 15%+starch 75%+oil 8%+vitamin mixture 1%+salt mixture 1% B group: pearl barley 98%+vitamin mixture 1%+salt mixture 1% C group: rice 98%+vitamin mixture 1%+salt mixture 1% D group: barley 98%+vitamin mixture 1%+salt mixture 1% E group: rice 49%+pearl barley 49%+vitamin mixture 1%+salt mixture 1% F group: rice 73.5%+pearl barley 24.5%+vitamin mixture 1% +salt mixture 1% G group: barley 49%+pearl barley 49%+vitamin mixture 1% +salt mixture 1% H group: barley 73.5%+Pearl barley 24.5%+vitamin mixture 1%+salt mixture 1% The rats were kept in an individual cage and were fed 8 different diets for 7 weeks and fed by ad-libitum feeding method. The results of this study were eluciated as followings. 1. B group was significantly lower in weight gain than the other groups. 2. Polished pearl barley showed higher digestion rate in protein and carbohydrate than brown pearl barley but lower in fat. 3. Liver weight was obserbed significant differences between B group and C group. but no significant differences between the others. 4. B group was significantly lower in the total protein content of liver and A/G ratio in plasma than other groups. 5. B group was also the lowest in the hematocrit and hemoglobin contents among the experimental groups. 6. Free amino acid composition in plasma was similar to those in diet.

• Journal of the Korea Computer Graphics Society
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• v.26 no.3
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• pp.123-131
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• 2020

This study proposes a real-time rendering algorithm for lighting when each of more than 100,000 moving particles exists as a light source. Two 3D textures are used to dynamically determine the range of influence of each light, and the first 3D texture has light color and the second 3D texture has light direction information. Each frame goes through two steps. The first step is to update the particle information required for 3D texture initialization and rendering based on the Compute shader. Convert the particle position to the sampling coordinates of the 3D texture, and based on this coordinate, update the colour sum of the particle lights affecting the corresponding voxels for the first 3D texture and the sum of the directional vectors from the corresponding voxels to the particle lights for the second 3D texture. The second stage operates on a general rendering pipeline. Based on the polygon world position to be rendered first, the exact sampling coordinates of the 3D texture updated in the first step are calculated. Since the sample coordinates correspond 1:1 to the size of the 3D texture and the size of the game world, use the world coordinates of the pixel as the sampling coordinates. Lighting process is carried out based on the color of the sampled pixel and the direction vector of the light. The 3D texture corresponds 1:1 to the actual game world and assumes a minimum unit of 1m, but in areas smaller than 1m, problems such as stairs caused by resolution restrictions occur. Interpolation and super sampling are performed during texture sampling to improve these problems. Measurements of the time taken to render a frame showed that 146 ms was spent on the forward lighting pipeline, 46 ms on the defered lighting pipeline when the number of particles was 262144, and 214 ms on the forward lighting pipeline and 104 ms on the deferred lighting pipeline when the number of particle lights was 1,024766.

• Journal of Environmental Science International
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• v.20 no.11
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• pp.1417-1423
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• 2011

For evaluating the effect of various organic fertilizer ratios on the Spiraea${\times}$bumalda 'Gold Mound' growth, a container green wall system experiment was conducted in a greenhouse at Konkuk university. The experimental planting grounds were prepared with different organic fertilizer ratios ($A_1L_0$, $A_8L_1$, $A_4L_1$ $A_2L_1$ and $A_1L_1$) and with drought tolerance and an ornamental value Spiraea${\times}$bumalda 'Gold Mound' was planted. The change in soil moisture contents, plant height, number of branches, number of dead leafs, number of leaf, number of shoots, length of node, length of leaf, width of leaf, root-collar caliper, chlorophyll contents and survival rate were investigated from April to Jun 2010. 1. The result of soil moisture contents was analyzed with weight unit in the container green wall system during the dry summer season. The soil moisture contents were significantly enhanced in the container green wall system in increasing order as the amount of fertilizer level increased $A_1L_1$ > $A_2L_1$ > $A_4L_1$ > $A_8L_1$ > $A_1L_0$. 2. Compared to the control treatment (amended soil with 100% + organic fertilizer 0%) application, the highest plant growth was observed in the treatment of $A_2L_1$(amended soil with 67% + organic fertilizer 13%) application. However, the differences between the organic fertilizer ratio treatments of $A_1L_1$, $A_4L_1$, $A_8L_1$, and the $A_1L_0$ organic fertilizer application were mostly not significant. 3. The survival rate increased with the increasing application of organic fertilizer, but in the control treatment (amended soil with 100% + organic fertilizer 0%) application all the plants died. Experimental results from the presented study clearly demonstrated that the organic fertilizer improved the survival rate more than the Spiraea${\times}$bumalda 'Gold Mound' growth at different levels of organic fertilizers. This strain can be utilized as a plant growth application in living wall systems during the dry summer season. Therefore, Spiraea${\times}$bumalda 'Gold Mound' is expected to be a highly valuable shrub for the green wall system if it should be considered in integration with stormwater retention or as a soil conditioner for increasing soil water contents in planting ground.

• Journal of the Korean Geotechnical Society
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• v.15 no.2
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• pp.43-71
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• 1999

This research is an experimental work of developing a construction material using municipal wastewater sludge as liner and cover materials for waste disposal landfill. Weathered granite soil and flyash, produced as a by-product in the power plant, were used as the primary additives to improve geotechnical engineering properties of sludge. For secondary additives, bentonite and cement were mixed with sludge to decrease the permeability and to increase the shear strength, respectively. Various laboratory test required to evaluate the design criteria for liner and cover materials, were carried out by changing the mixing ratio of sludge with the additives. Basic soil properties such as specific gravity, grain size distribution, liquid and plastic limits were measured to analyze their effects on permeability, compaction, compressibility and shear strength properties of mixtures. Laboratory compaction tests were conducted to find the maximum dry densities and the optimum moisture contents of mixtures, and their effectiveness of compaction in field was consequently evaluated. Permeability tests of variable heads with compacted samples, and the stress-controlled consolidation tests with measuring permeabilities of samples during consolidation process were performed to obtain permeability, and to find the compressibility as well as consolidational coefficients of mixtures, respectively. To evaluate the long term stability of sludges, creep tests were also conducted in parallel with permeability tests of variable heads. On the other hand, for the compacted sludge decomposed for a month, permeability tests were carried out to investigate the effect of decomposition of organic matters in sludges on its permeability. Direct shear tests were performed to evaluate the shear strength parameters of mixed sludge with weathered granite, flyash and bentonite. For the mixture of sludge with cement, unconfined compression tests were carried out to find their strength with varying mixing ratio and curing time. On the other hand, CBR tests for compacted specimen were also conducted to evaluate the trafficability of mixtures. Various test results with mixtures were assessed to evaluate whether their properties meet the requirements as liner and cover materials in waste disposal landfill.

• Journal of Intelligence and Information Systems
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• v.20 no.2
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• pp.149-162
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• 2014

Course guidance is a mentoring process which is performed before students register for coming classes. The course guidance plays a very important role to students in checking degree audits of students and mentoring classes which will be taken in coming semester. Also, it is intimately involved with a graduation assessment or a completion of ABEEK certification. Currently, course guidance is manually performed by some advisers at most of universities in Korea because they have no electronic systems for the course guidance. By the lack of the systems, the advisers should analyze each degree audit of students and curriculum information of their own departments. This process often causes the human error during the course guidance process due to the complexity of the process. The electronic system thus is essential to avoid the human error for the course guidance. If the relation data model-based system is applied to the mentoring process, then the problems in manual way can be solved. However, the relational data model-based systems have some limitations. Curriculums of a department and certification systems can be changed depending on a new policy of a university or surrounding environments. If the curriculums and the systems are changed, a scheme of the existing system should be changed in accordance with the variations. It is also not sufficient to provide semantic search due to the difficulty of extracting semantic relationships between subjects. In this paper, we model a course mentoring ontology based on the analysis of a curriculum of computer science department, a structure of degree audit, and ABEEK certification. Ontology-based course guidance system is also proposed to overcome the limitation of the existing methods and to provide the effectiveness of course mentoring process for both of advisors and students. In the proposed system, all data of the system consists of ontology instances. To create ontology instances, ontology population module is developed by using JENA framework which is for building semantic web and linked data applications. In the ontology population module, the mapping rules to connect parts of degree audit to certain parts of course mentoring ontology are designed. All ontology instances are generated based on degree audits of students who participate in course mentoring test. The generated instances are saved to JENA TDB as a triple repository after an inference process using JENA inference engine. A user interface for course guidance is implemented by using Java and JENA framework. Once a advisor or a student input student's information such as student name and student number at an information request form in user interface, the proposed system provides mentoring results based on a degree audit of current student and rules to check scores for each part of a curriculum such as special cultural subject, major subject, and MSC subject containing math and basic science. Recall and precision are used to evaluate the performance of the proposed system. The recall is used to check that the proposed system retrieves all relevant subjects. The precision is used to check whether the retrieved subjects are relevant to the mentoring results. An officer of computer science department attends the verification on the results derived from the proposed system. Experimental results using real data of the participating students show that the proposed course guidance system based on course mentoring ontology provides correct course mentoring results to students at all times. Advisors can also reduce their time cost to analyze a degree audit of corresponding student and to calculate each score for the each part. As a result, the proposed system based on ontology techniques solves the difficulty of mentoring methods in manual way and the proposed system derive correct mentoring results as human conduct.

• Management & Information Systems Review
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• v.36 no.3
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• pp.37-49
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• 2017

This study investigates the dynamic relationship between KOSPI200 stock index and stock index futures and stock index option markets which is its derived from KOSPI200 stock index. We use 5-minutes rate of return data from 2012. 06 to 2014. 12. To empirical analysis, this study use autocorrelation and cross-correlation analysis as a preliminary analysis and then following Stoll and Whaley(1990) and Chan(1992), the multiple regression is estimated to examine the lead-lag patterns between the stock index and stock index futures and option markets by Newey and West's(1987) Empirical results of our study shows as follows. First, there exist a strong autocorrelation in the KOSPI200 stock index before 10minutes but a very weak autocorrelation in the stock index futures and option markets. Second, there is a strong evidence that stock index future and option markets lead KOSPI200 stock index in the cross-correlation analysis. Third, based on the multiple regression, the stock index futures and option markets lead the stock index prior to 10-15 minutes and weak evidence that the stock index leads the future and option markets. This results show that the market efficient of KOSPI200 stock index market is improved as compared to the early stage of stock index future and option market.

• Journal of Korea Society of Industrial Information Systems
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• v.12 no.5
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• pp.1-13
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• 2007

In this research, we found out that bridging nodes have great effect on the robustness of protein-protein interaction networks. Until now, many researchers have focused on node's degree as node's essentiality. Hub nodes in the scale-free network are very essential in the network robustness. Some researchers have tried to relate node's essentiality with node's betweenness centrality. These approaches with betweenness centrality are reasonable but there is a positive relation between node's degree and betweenness centrality value. So, there are no differences between two approaches. We first define a bridging node as the node with low connectivity and high betweenness value, we then verify that such a bridging node is a primary factor in the network robustness. For a biological network database from Internet, we demonstrate that the removal of bridging nodes defragment an entire network severally and the importance of the bridging nodes in the network robustness.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.233-241
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• 2016

Experiments were carried out to quantify the topographic effects on attenuation of sunshine in complex terrain and the results are expected to help convert the coarse resolution sunshine duration information provided by the Korea Meteorological Administration (KMA) into a detailed map reflecting the terrain characteristics of mountainous watershed. Hourly shaded relief images for one year, each pixel consisting of 0 to 255 brightness value, were constructed by applying techniques of shadow modeling and skyline analysis to the 3m resolution digital elevation model for an experimental watershed on the southern slope of Mt. Jiri in Korea. By using a bimetal sunshine recorder, sunshine duration was measured at three points with different terrain conditions in the watershed from May 15, 2015 to May 14, 2016. The brightness values of the 3 corresponding pixel points on the shaded relief map were extracted and regressed to the measured sunshine duration, resulting in a brightness-sunshine duration response curve for a clear day. We devised a method to calibrate this curve equation according to sky condition categorized by cloud amount and used it to derive an empirical model for estimating sunshine duration over a complex terrain. When the performance of this model was compared with a conventional scheme for estimating sunshine duration over a horizontal plane, the estimation bias was improved remarkably and the root mean square error for daily sunshine hour was 1.7hr, which is a reduction by 37% from the conventional method. In order to apply this model to a given area, the clear-sky sunshine duration of each pixel should be produced on hourly intervals first, by driving the curve equation with the hourly shaded relief image of the area. Next, the cloud effect is corrected by 3-hourly 'sky condition' of the KMA digital forecast products. Finally, daily sunshine hour can be obtained by accumulating the hourly sunshine duration. A detailed sunshine duration distribution of 3m horizontal resolution was obtained by applying this procedure to the experimental watershed.

• Journal of Korean Home Economics Education Association
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• v.20 no.4
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• pp.223-237
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• 2008

The purpose of this research was to provide the information needed for improving the contents in housing unit of middle school technology and home economic textbook. For this purpose, a survey questionnaire was developed to examine teachers' importance perception of 48 contents in housing unit. A direct survey and an e-mail survey were used to collect data from teachers, and a total number of 233 data were analyzed. Conclusions were summarized as following: 1. Among the 48 contents in housing unit, the average score of teachers' importance perception of the 18 contents on 'interior environment and equipments' was 3.94; the average score of teachers' importance perception of the 15 contents on 'living space plan and use' was 3.78; and the average score of teachers'importance perception of the 15 content on 'housing maintenance and repair' was 3.42. Therefore, the 15 contents on 'housing maintenance and repair' must be revised. 2. Teachers' importance perception of 25 contents, among the 48 contents in housing unit, were significantly differentiated by gender, age, teaching experience, scholastic attainment, subject in charge(technology, home economics, technology and home economics), school type(boys' middle school, girls' middle school, coeducation), and region(city, county). Therefore, the 25 contents, of which importance perception were influenced by teachers' characteristics, must be revised in order to maintain the consistent importance perception. Suggestions were that the team teaching of technology and home economic textbook was more recommendable; that the local situations must be considered in the contents of housing unit and; that the contents of housing unit must be segmented into a minimum unit for the accurate evaluation.